Maine is generally fine (assuming you mean the section east of 14th, since you say you’re coming from West Potomac Park). The sidewalk from 14th to the fish market is very wide, but a lot of tour buses drop off there, so there can be lots of oblivious peds and idiot drivers turning into the fish market parking lot. Most eastbound riders take the street and it’s not bad at all since traffic slows around the entrance to the fish market. Once you pass the fish market, I recommend hopping on Water street, which will take you all the way to the ART connecter to P street. Once you hit P street, you’re golden…it kinda has a slightly sketchy feel once you pass Fort McNair, but I’ve never had any problems riding through there. Since the bike valet (pretty much the best service ever) is at the NE corner of the stadium and there will be a LOT of peds on S. Capitol and on N, I recommend crossing S. Capitol at P street, turning right and riding down to Potomac, then taking that up to 1st/N where the valet is. Kinda roundabout, but probably easier…